javascript全局变量封装模块实今世码

下面的代码是我的测试代码,注释很重要: 复制代码 代码如下: /*global
window,jQuery,validate_email,masterUI,$,rest*/ /** Enable ECMAScript
“strict” operation for this function. See more: *
*

* Q1: Why are window and document being fed instead of just being
accessed normally? * A1: Generally to fasten the identifier resolution
process, having them as local variables can help (although IMO the
performance improvements may be negligible). *金沙8331网址, A2: Passing the global
object is also a widely used technique on non-browser environments,
where you don’t have a window identifier at the global scope, e.g.: * {
* //.. * }); // this on the global execution context is the global
object itself * A3: Passing window and document allows the script to be
more efficiently minified * * Q2: Why the heck is undefined being
passed in? * A1: This is made because the undefined global property in
ECMAScript 3, is mutable, meaning that someone could change its value
affecting your code, for example: * undefined = true; // mutable * {
* alert; // “undefined”, the local identifier * })(); // 复制代码
代码如下: [plain] view plaincopyprint?

下面的代码是我的测试代码,注释很重要:

AppEngine SDK

复制代码 代码如下:

3.Jslint会报两个问题,一是关于undefined的,没找到什么好方法,任它抱怨吧。另一格式最后调用方式要改成:
复制代码 代码如下: [javascript] view
plaincopyprint?}; }; 无所谓了,就任由它吧。只要功能正常就行。

/*global window,jQuery,validate_email,masterUI,$,rest*/
/** Enable ECMAScript “strict” operation for this function. See
more:
*
*

* Q1: Why are window and document being fed instead of just being
accessed normally?
* A1: Generally to fasten the identifier resolution process, having
them as local variables can help (although IMO the performance
improvements may be negligible).
* A2: Passing the global object is also a widely used technique on
non-browser environments, where you don’t have a window identifier at
the global scope, e.g.:
* (function (global) {
* //..
* })(this); // this on the global execution context is the global
object itself
* A3: Passing window and document allows the script to be more
efficiently minified
*
* Q2: Why the heck is undefined being passed in?
* A1: This is made because the undefined global property in ECMAScript
3, is mutable, meaning that someone could change its value affecting
your code, for example:
* undefined = true; // mutable
* (function (undefined) {
* alert(typeof undefined); // “undefined”, the local identifier
* })(); // <– no value passed, undefined by default
* If you look carefully undefined is actually not being passed (there’s
no argument on the function call),
* that’s one of the reliable ways to get the undefined value, without
using the property window.undefined.
*
*/
(function(window, document, undefined) {
“use strict”;
window.test = {
init: function () {
“use strict”;
alert(“ok”);
}
};
})(window, document);// no undefined parameter here to avoid using
mutable window.undefined changed by other guy

1.说明,参考了一篇文章和stackoverflow上的一个帖子
2.(function(){})()
这种代码写在独立的js文件里,当js文件被html加载的时候,该函数就会执行。实际上创建了windows.text对象。
以后html代码就可用test.init的形式调用方法。
测试html部分代码如下:

复制代码 代码如下:

[plain] view plaincopyprint?
<head>
<title>AppEngine SDK</title>
<meta http-equiv=”Content-Type” content=”text/html;
charset=UTF-8″>
<script type=”text/javascript”
src=”../../master/script/third_party/jquery-1.8.0.min.js”></script>
<script type=”text/javascript”
src=”../../master/plugin/jquery-validation-1.9.0/jquery.validate.js”></script>
<script type=”text/javascript”
src=”../../master/plugin/artDialog4.1.6/jquery.artDialog.js”></script>
<script type=”text/javascript”
src=”../../master/script/app/test.js”></script>
<script type=”text/javascript”>
$(document).ready(function() {
test.init();
})
</script>
</head>

3.Jslint会报两个问题,一是关于undefined的,没找到什么好方法,任它抱怨吧。另一格式最后调用方式要改成:

复制代码 代码如下:

[javascript] view plaincopyprint?}(window, document)); }(window,
document));

无所谓了,就任由它吧。只要功能正常就行。

复制代码
代码如下: /*global window,jQuery,validate_email,masterUI,$,rest*/
/** Enable ECMAScript “strict” operation…

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